Piezoelectric high voltage devices of both the impact type and gradual squeeze type are known in the prior art. There are various means of assembling or mounting the piezoelectric element or elements. In some cases, thin soft metal wafers are placed between each end of each piezoelectric element and the associated metallic adjacent end means. These adjacent end means are often identified as impact pin and anvil means. In other cases the piezoelectric elements and associated impact and anvil means are molded in a plastic body.
In some cases the piezoelectric elements and impact pin and anvil means are held loosely in an insulating body and encapsulated in epoxy or other relatively hard insulating material. Various materials have been used in connection with piezoelectric elements, including silicone oil, silicone grease, and rubber. These materials have been utilized to create a damping effect.
A persistent problem which has existed in the art associated with the use of piezoelectric ignition devices has been the operating life, especially over a wide temperature range, of such devices. There is a need for piezoelectric high voltage devices which survive a greater number of ignitions than have heretofore been available. The present invention addresses this problem and provides a piezoelectric high voltage mechanism which enjoys a vastly superior operating life than devices previously used.
It is therefore a primary object of the present invention to provide a new and improved high voltage piezoelectric mechanism that alleviates the aforementioned difficulties in the art. It is a further object of this invention to provide such a new and improved high voltage piezoelectric mechanism which is constructed in a relatively simple and efficient manner. Another object of the invention is to provide a high voltage piezoelectric mechanism which has a long and reliable operating life. Yet another object of this invention is to provide a high voltage piezoelectric mechanism which has superior operating characteristics over a wide temperature range.
It is also an object of this invention to provide an encapsulation for high voltage piezoelectric mechanism which assures long and reliable operating life. It is a further object to provide by this means superior operating characteristics over a wide temperature range. Another object of this invention is to provide an encapsulation for high voltage piezoelectric mechanisms which allows use of piezoelectric elements without nearly perfect plane and parallel load surfaces. A further object of this invention is to provide an encapsulation for high voltage piezoelectric mechanisms which prevents dielectric breakdown or leakage across the surface of the piezoelectric element or between the internal electrodes of the high voltage mechanism.
Other objects, uses, advantages and novel features of this invention will be set forth in part in the description which follows and in part will be obvious from the description or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities, combinations and materials particularly pointed out in the appended claims.